Just like the Jesus Illusion, you'll stare at this picture for 30 seconds and then stare at a blank wall. The wall doesn't have to be white, but we've found it works better with lighter colors. You can also stare at the white space next to the illusion on your computer monitor, or at a blank piece of paper on your desk.

For you to experience the strongest illusion, you'll want to stare at the center of the red plus sign. Don't move your head, and really try not to move your eyes at all. We've found that a plus sign allows your eyes to move ever so slightly, but you should be able to keep them centered.

Artist who goes by the name DigitEL sent me this incredible photo. My guess was that it happened by accident, but the effect is extraordinary! DigitEl said the same thing: “Here is one that kind of snuck up while photographing the red foliage hedge. I have always taken variations of a view with poles, wires, and other shadows included, but it was not until looking at the captured image… made me suddenly grin at the play between tree trunk shadow and the red hedge. Enjoy!”

The watercolor effect inspired the wave-line illusion by Japanese vision scientist Seiyu Sohmiya. In this version, professor Akiyoshi Kitaoka shows that the white background behind the pattern is tinged by the color of the waves. It looks as if the orange wave has different background color than purple wave, while in fact both backgrounds are purely white!